Combustion-engine.



J.. SULZER., GMBUSTON ENGINE. APPLIUATIO'N Hman JAN. 21, 1911.

Lmgygyb lftented May 19, 1914:.

Pis 'n veil HNEMTQR mechanism imin'ored.

PATENT @lhllilljti Specification of Letters Patent.

Patented May t9, Emiel.

ivpplcatonvled January 21, 19H. Serial No. 693,949.

To all whom it may oonom'n Be it known that it? JAnon SULZER, engineer.; a eitizen of the Swiss Republic, residing.; at 'Si' tianggoeee, iiVinterthnrj Sn'itvzer lendj 'here invented eertoin new and useful linpi'oveinento in oinhnstion- Engines; and l. do hereby declare the following to be a toll, Clear, and exact description of the ini'entioin finch as will enable others skilled in the art to which. is oppertains to make und noe the sanne. n

Thi* :ini'entioii an improvement in nir starting end reversing ineohanisn'is 'for eenibostion engines and consists in an arrangement of volvo-gearing tor controlling` the `conditions ot admission of compressed-oir to the eoinbnstiim eylinder or Cylinders.` whe; the supply et Snell air is eoneerved. one me ntiiity'aifnl general ellieieney et the l 'iihese results a re bi'onglit about in part5 .aeeordinev to the present invention, by controlling the air adiniosion charges;l throughout their Whole range of yoiiatiim troni niaxinnnn charge inininnnn charge eo that they will enter tl,` ;lindei' always'elose to the dead center ifoint, not the "loei of the piston loweot, passageway that is leest enh] ietioin the said results heiligu also arizona lished in part, by the ar- "i'oiigeinent et t 3 nietos the .point et admission to the cylinder et less than the maximum compressed air ehorges is later 1than the point ot admission of the inaxiinlnn charge, and hence while the piston is moving more rapidly, so that more or less of a throttline -action is apparent upon the paosage. ofthe air, with consequent loss of eflieieney.

The present vimfeietion eliminates the obvious objections accruing in existing meehanisnls from these and other Causes and thereby aeeomplishe the same ultimate effect with consequent substantial saving of the eompreoeed lair, Whiehis et' importance es ecially in marine and locomotive power o onto. l

"the invention Wlil be more readily unm derstood by reference to the drawings wherein-- lgnre l illustrates a portion of'an en- `eine cylinder `with starting mechanism et this invention applied thereto; Fig. 2, on the nighthand eide7 a diagram in polar eordinales,' ot the Yalve-lii`t curves of the starting` mechanism oit' an ordinary engine, not involving this invention, and on the lel'thand Side ,shows the expansion enrves eorresrionding to the indicated volvo-lifts thereof; Fig. 3 :i similar diagram of: \'al\'e-lit`ts and .result-ing expansion curves of startiiig-mechanism employing; this invention, and noch as :nay be produced by the use ot apparatlh` indicated by Figi l. in the (litigi-alim oi Figs. i2 and 3 the tol'- ward dii'eetion oi the eranlt Soa'it rotation is assumed to be as nnirlieiil by the arrows.

Referring first to `f`if. l, o represents the Starting 'valve oi. o ron'ilnlsiion engine to which compressed air supplied by a een duit e. This valve io operated by a Valvelevei' journaled on an eeeentrie tulo/ruin o whirl) van be shifted by reciting; its exis by the handle Shown. The .'al'velever actie ated by the vain o7 oit an engine-driven Cain shaft oo an to open the starting valve :it the pro-pei' linie and with a greater or lees degree ot lift according` to the adjnetinent oit 'the lshiftable nlerinn; [te thus tor de- .seribed the construction is the saine in prineiple as manly etartinp'vgears he ofoie proposed and the parts above 'red to niay theretoi'e he asienined to represent the parts for carrying` ont the tunetions represented by the diagram in Fig. 9. l.Vith these parte the present invention eenibines a secondary or aiixiliary air-valve g in a suitable auxiliary air ehoinber or valve waning and which controls the passage oi compressed air from the supply conduit i to the pipe e and the other valve. Thin seeondary volvo is .provided with the necessary trici-ion roller and spring to enable it to be opened and Closed by the @am 71, also mounted on the Cain shaft in a different plane from the com d. The two come eenm trol the valves a and `g in sneh manner as that one, for example, a, will remain open from a. point at one side of the deed center to a point equally spaced therefrom on the opposite eide while the other will open at represented by the outer curved line, marked max. charge and, the open period, as will be observed, extends from a point just in advance of theupper dead center to a point just in advance of the exhaust, thus providing for the 1naximum volume of compressed air admission. The radius-vector m-a which bisects this curve, represents Yits axis and all lesser degrees of valve lift will also be found to be substantially bilsected by the same axis, that isto say, will besymmetrical thereto.` Thus, as shown by the diagram, the next inner curve, marked red, shows a reduced or intermediate valve-lift and thecurve marked min. shows a minimum valve-lift. The axis of symmetry for each of these valve-lifts,vbeing substantially the same for all, assumes an angle onthe diagram corresponding to a' point in the working cycle about midway between the upper dead center point, where the piston is stationary, and the midstroke point where it is ,moving at its highest velocity. The corresponding pressure effects, forV the position of the axis of symmetry are shown by the card diagrams projected to the lefthand side of Fig. 2, where the relative pressure is indicated in atmospheres.

The Obliquity of the axis of symmetry, it may be here explained, arises from the necessity of employing maximum air charges of mostly above 60% of the cylinder volume, in order to'start engines from any crank position, the consequence of which, is that in reducing the charge, the closing and opening actions of the valve (valve a) both occur more vclosely to this line of symmetry, so that as a result of the retarded opening action, and the throttling effect during the admission (by virtue of the coincident piston velocity) as well as the retarded closing of the valve, the pressure diagrams, as projected atthe lefthand side of Fig 2, show an insufiicient utilization of the compressed air energy. From the diagram it will be immediately seen that as the valve lift isl decreased, a reduction in the consumption of compressed air takes place only to a very limited extent, the pressure of the air being still relatively high, when exhaust ing.

Fig. 3 shows as already stated how the defects of the starting gear as illustrated by Fig. 2 arc obviated. According to this in-v Loewe? vention, the admission of air to the working cylinder is attained by the coperation of `both valves a g. The cam al controls the starting valve proper, (valve a) and the cam z controlsthe intermediate or secondary starting valve (valve g). The latter valve g is controlled, z'. e., opened and closed without variation and the valve-lift thereof corresponds in point oftime and extent to thev for its individual charges coincides with the dead-center line whichin Fig. 3 is indicated by the line 0 7?. The result attained thereby is, on the one hand, that the main valve a is already fullypopen in the dead-center position for all charges so that therefore the opening of the air inlet to the cylinder is effected always in the dead-center position by the .intermediate valve g and on the other hand that in using the invention "for reversible combustion engines a reversal of all of the main valves a, in a multicylinder engine for example, as avoided.` The direction of the engine may'thus be varied solely bythe operation of the intermediate valves without danger of interfering with the controllability of the starting gear, The closing of the main valves, both for forward and backward running of the engine, takes place symmetrically to the dead-center line and hence with only a negligible throttling effect because of the low piston velocity at this point. That is to say, such throttling of the incoming compressed air is without effect for the reason that the range of the valve lift is moved close tothe dead-center and therefore Aclose to the period of the smallest piston velocity, whereas in the case of Fig.' 2 the area representing the valve elevation for small charges lies toward 'the center of the stroke, that is to say, near the greatest velocity of the piston. It is moreover to be noted that the valve a. may remain open during the complete revolution of the controlling shaft le when the roller on the lever ZJ by corresponding adjustment of the eccentric 0 is moved down to the circular base of the cam d, and that a reduction of the valve-throw and of the valve lifting du rat-ion takes place When the roller on the lever b is lifted away from the cam (l.

ln Fig. 3 the valve lifting extents are indicatedY inthe same manner as in Fig. 2, first of all without the reduction due to the cam and then with increasing reduction of the charge effected bythe cam d. The coperation of the main. valve a with the auxiliary 'valve g characterized in all conditions oft the regulation by the *fact that the opening action for admitting air to the cylinder by means oit the auxiliary valve g occurs inra constant manner prior to the ripper deadcen er whereas the nt-eti of the air inlet by the main 'valve a occurs at variable distances ot the piston trom the upper dead-center point. Fig. 3 shows clearly that all of the salve closing stages due to the action of the main valve occupy a position between the stroke center and the upper dead-center point es distinguished/from Fig. 2 wherein the valve elosinof stagesl occur between stroke center lower deadcenter point, which in the diagram is expressed by the increased degree of expansion of the starting air. A. comparison with Fig. 2 'will indicate the superior pressure -eii'ects attained by this invention and particularly the average diminntion oft the exhaust pressures.

.'Qhus in combustion engines working with, or started ley-means of, compressed air the present invention enables a complete utilization oi the compressed air energy to be attained, and with small air charges, by causing on the one hand the admission of the starting air to take place in the period of the lowest piston velocity and smallest throttling and on the other hand by increasing the deA grec of expansion of the starting air for decreasing charges in proportion to the decrease ot thef charge.

Means for operating combustion engines with compressed air comprising two independent vaives for controiling the admission of. compressed air to the engines, means for operating one of such valves with a uniform lift and a period which includes a portion of the working stroke and means for operating the other valve with a variable litt and a period which extends over substantially eqnai portions of theengine cycle before and subsequent to the dead center point.

Q. in a combustion engine, starting mechanism comprising two Valves, an inlet tothe ie cylinder controlled thereby, an endriren cam shaft for operating both sneh 'valves and means for variably controlling the operation of one of such valves.

ii. stir-starting mechanism for combns. tion engines comprising an inletV passage to L" r "ine cylinden two Valves in control t t3 thereo., and engine driven means Ifor operating such valves with. open periods which overlap between the dead 'center and midstroke points ot the cycle.

4. in a combustion engine started by compressed air, a conduit leading from a source of compressed air to the cylinder of the engine, a Valve controlling the admission of air from said conduit, a valve controlling the admission of air to said conduit, means for opening said first mentioned valve and means for controlling at will gthe time of opening said first mentioned valve relatively to the position or" the piston of the engine all substantially as described and 'for the purpose speciiied.

ln air-starting mechanism for combustion engines, a conduitV tor admitting eomf pressed air to the engine cylinder and two Valves for controlling the passage of air therethrough, in comblnation with valve operating .means adapted to open one of such valves with an open period symmetrically arranged with respect to the dead center vpoint and the other with an open period co incident with a portion of the expansion or working stroke, and means for Varying the air admission through the first-mentioned valve.

6. In a combustion engine adapted to be started by compressed. air, the combination of an air conduit, a valve controlling the connection of such conduit with the engine cylinder and proijided with means for varying the extent to which it opens, a second valve controlling the admission of air to said conduit and means for holding said valve open during the major portion of each working stroke.

7. in a combustion engine started by compressed air, the combination of a cylinder valve oontroiling admission of starting air to the cylinder, a Valve lever therefor mounted on an adjustable ulcrum, a second valve controlling the passage of compressed air to the said cylinder valve, means for holding said second valve open during a majo'rportion of each working strokeV and means for .shifting the fulcrumof the Valve lever.

in testimony whereof Iphave affixed my signature, in presence of two witnesses.

JAKOB SULZER.

Witnesses CARL Coenen, Trinonon Rnrrrnn. 

